atcomsystems.ca/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems A little bit of insight on 1A2 for the "younguns"

There were several different ways that intercom was handled, but most used single-path intercom systems. An open talk path was wired to a dedicated line button (key) on the phones. There was no dial tone, just talk battery. You could then dial the single or double-digit intercom button and it would sound the buzzer in the called phone for 1-2 seconds. There was no privacy on intercom calls, in fact two people or more could pick up and talk to each other without dialing anything at all.

There were more sophisticated intercom systems that offered multiple talk paths, dial tone and repeated buzzing/ringing of the phones but they were much more complex to install/maintain and very expensive to rent from the telco.

Don't forget the good ol' buttons and buzzers Ed. That could drive you bananas on a large system.

Any of you guys ever get an invite to the MELCO train?
They had 2 cars. A luggage car with washer, dryer, diesel powerplant water holding tanks. And everything that Melco made, mounted on 1 wall so they could demo and you could play with it.
Then they had an observation car with 2 bedrooms and a full mini kitchen, Oh, and a VERY hospitable bar! If I recall correctly, they said they had enough fuel and water to survive for 1 week, as long as they had access to a grocery source.
And, of course, some kid set fire to it while it was 'at home' in Washington state. The whole thing was a tax write off, and I was told the owner of Melco was a train nut. I get jealous thinking about it today!

John C.

Aw c'mon Ed, be brave..... don't you remember the 6A intercom system?

Strangest thing I remmember. One store had a full 1a2 style phone system with rotary phones and dial intercom, Automatic Electric if I remember correctly, yet none of the lines connected to the phone company! The owner had some kind of dispute with ma bell and would not install their equipment, instead two phone lines went directly into the office where the two phone systems met. Accoustic couplers allowed the handset of the phone to communicate with the phone system. Anyone could call any extension, but dialing 98 0r 99 connected you to the office, where you could tell the secretary who you wanted to call. She dialed the number then set the phone down. If you finished a buzzer rang and the secretary hung up. What a wierd system! Odder still it was working that way in 1986! Never got to see the switching equipment used. A few years later the place was bulldozed for an expressway exit. I remember how fully the desk phones looked!

Did Valcom buy the rights from Melco on the rt 19 and 36 intercoms? I think they must have the units are basically the same. Any thoughts?

Charlie:

I don't think that Valcom bought the rights to these things, I think that Melco just discontinued the R, T and RT units when Augat bought them in the early 1980's.

Remember that Tone Commander, Teltone and Melco were huge suppliers of these things to Bell companies and independent telcos, while Valcom catered more to interconnects. I think the fact that telcos dropped these things like a hot potato (after divestiture) made Valcom appear to have been the sole survivor.

For the most part, Valcom and ITT were in fact the only companies who continued making 1A2 intercom equipment after at the time. I think it's safe to say that Valcom is the only remaining manufacturer of these things but it's been over five years since I have purchased one so I can't say for sure.....

I installed Tone Commander MH 4000's at many sites in Turkey. They were the perfect substitute for a C.O. switch.

The systems enabled the troops to call from one office or room to another and we connected the autovon lines to them so they could call any base in Turkey from any phone on site.

Before we installed them the troops had to go to the radio building for phone calls which was usually some distance from the barracks. And you can imagine the Site Commanders would get important phone calls all hours of the night and they didn't like having to get dressed as they ran out into freezing weather in the middle of the night.
They sure were glad to see us arrive with the truck loaded with boxes labeled Tone Commander. Word got out quick from one remote site to another. We drink lots of free beers before leaving each site. :toast:

Thanks Ed.
I remember about 25 years ago I was thrown into learning 1a2. Lots of 620's and grave stones. I said, how the hell am I going to learn this mess.

I would get comments back then like, Do you know what you are doing? You look a bit young to be working on this... ect ect...Ive got to thank those old timers who used to say. "you can be a hacker or a slasher or you can learn 1a2"

Bobby: Do you mean ML-8000's? I do remember that there were tons of them around here as well and if I recall correctly, there was a CO line interface card that sounds like what you were doing with them.